<!DOCTYPE html>
<p>There should be a green square below, and no red.</p>
<div style="columns:2; column-gap:0; column-fill:auto; width:400px; height:200px;">
    <div style="height:200px;"></div>
    <div style="position:relative; overflow:hidden; height:100px;">
        <div style="width:100px; height:100px; background:red;"></div>
        <div style="position:absolute; left:0; top:0; width:100px; height:100px; background:green;"></div>
    </div>
</div>
